Variable oscillator for code practice (CB7317E)

This circuit is from Popular Electronics from the 90s. The integrated circuit is not very common nowadays.

Luminus SST 20 Deep Red LED
Luminus SST 20 Deep Red LED Mouser Electronics is announcing in its stock the SST-20, a 60%...
4093 Continuity Tester (CB25004E)
This 4093 IC continuity tester was found in the November 1986 Radio Electronics magazine. The...
PLL AM receiver (CB8633E)
This receiver circuit was found in a Hands On Electronics from the 90s. The circuit uses a PLL...